最近，我将我的数据库从localhost移到了一个在线数据库中。我的localhost一切正常。我没有更改除url之外的任何代码。为什么我现在面对这个错误，因为它之前没有出现？
logcat的：
03-17 04:15:26.370: E/AndroidRuntime(804): FATAL EXCEPTION: AsyncTask #3
03-17 04:15:26.370: E/AndroidRuntime(804): java.lang.RuntimeException: An error occured while executing doInBackground()
03-17 04:15:26.370: E/AndroidRuntime(804): at android.os.AsyncTask$3.done(AsyncTask.java:299)
03-17 04:15:26.370: E/AndroidRuntime(804): at java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:352)
03-17 04:15:26.370: E/AndroidRuntime(804): at java.util.concurrent.FutureTask.setException(FutureTask.java:219)
03-17 04:15:26.370: E/AndroidRuntime(804): at java.util.concurrent.FutureTask.run(FutureTask.java:239)
03-17 04:15:26.370: E/AndroidRuntime(804): at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:230)
03-17 04:15:26.370: E/AndroidRuntime(804): at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1080)
03-17 04:15:26.370: E/AndroidRuntime(804): at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:573)
03-17 04:15:26.370: E/AndroidRuntime(804): at java.lang.Thread.run(Thread.java:841)
03-17 04:15:26.370: E/AndroidRuntime(804): Caused by: android.view.ViewRootImpl$CalledFromWrongThreadException: Only the original thread that created a view hierarchy can touch its views.
03-17 04:15:26.370: E/AndroidRuntime(804): at android.view.ViewRootImpl.checkThread(ViewRootImpl.java:5908)
03-17 04:15:26.370: E/AndroidRuntime(804): at android.view.ViewRootImpl.invalidateChildInParent(ViewRootImpl.java:869)
03-17 04:15:26.370: E/AndroidRuntime(804): at android.view.ViewGroup.invalidateChild(ViewGroup.java:4253)
03-17 04:15:26.370: E/AndroidRuntime(804): at android.view.View.invalidate(View.java:10482)
03-17 04:15:26.370: E/AndroidRuntime(804): at android.widget.TextView.invalidateRegion(TextView.java:4591)
03-17 04:15:26.370: E/AndroidRuntime(804): at android.widget.TextView.invalidateCursor(TextView.java:4534)
03-17 04:15:26.370: E/AndroidRuntime(804): at android.widget.TextView.spanChange(TextView.java:7412)
03-17 04:15:26.370: E/AndroidRuntime(804): at android.widget.TextView$ChangeWatcher.onSpanAdded(TextView.java:9103)
03-17 04:15:26.370: E/AndroidRuntime(804): at android.text.SpannableStringBuilder.sendSpanAdded(SpannableStringBuilder.java:979)
03-17 04:15:26.370: E/AndroidRuntime(804): at android.text.SpannableStringBuilder.setSpan(SpannableStringBuilder.java:688)
03-17 04:15:26.370: E/AndroidRuntime(804): at android.text.SpannableStringBuilder.setSpan(SpannableStringBuilder.java:588)
03-17 04:15:26.370: E/AndroidRuntime(804): at android.text.Selection.setSelection(Selection.java:76)
03-17 04:15:26.370: E/AndroidRuntime(804): at android.text.Selection.setSelection(Selection.java:87)
03-17 04:15:26.370: E/AndroidRuntime(804): at android.text.method.ArrowKeyMovementMethod.initialize(ArrowKeyMovementMethod.java:302)
03-17 04:15:26.370: E/AndroidRuntime(804): at android.widget.TextView.setText(TextView.java:3759)
03-17 04:15:26.370: E/AndroidRuntime(804): at android.widget.TextView.setText(TextView.java:3629)
03-17 04:15:26.370: E/AndroidRuntime(804): at android.widget.EditText.setText(EditText.java:80)
03-17 04:15:26.370: E/AndroidRuntime(804): at android.widget.TextView.setText(TextView.java:3604)
03-17 04:15:26.370: E/AndroidRuntime(804): at my.fyp.inticlassifieds.DisplayItemInfoEdit$GetProductDetails.doInBackground(DisplayItemInfoEdit.java:175)
03-17 04:15:26.370: E/AndroidRuntime(804): at my.fyp.inticlassifieds.DisplayItemInfoEdit$GetProductDetails.doInBackground(DisplayItemInfoEdit.java:1)
03-17 04:15:26.370: E/AndroidRuntime(804): at android.os.AsyncTask$2.call(AsyncTask.java:287)
03-17 04:15:26.370: E/AndroidRuntime(804): at java.util.concurrent.FutureTask.run(FutureTask.java:234)
03-17 04:15:26.370: E/AndroidRuntime(804): ... 4 more
类别：
public class DisplayItemInfoEdit extends Activity {
EditText txtName;
EditText txtPrice;
EditText txtDesc;
EditText txtCreatedAt;
Button btnSave;
Button btnCancel;
Spinner requeststatus;
String pid;
// Progress Dialog
private ProgressDialog pDialog;
// JSON parser class
JSONParser jsonParser = new JSONParser();
// single product url
//private static final String url_product_detials = "http://10.0.2.2:8000/project/get_item_info.php";
private static final String url_product_detials = "http://inticlassifields.comze.com/phpscripts/get_item_info.php";
// url to update product
//private static final String url_update_product = "http://10.0.2.2:8000/project/update_item.php";
private static final String url_update_product = "http://inticlassifields.comze.com/phpscripts/update_item.php";
// JSON Node names
private static final String TAG_SUCCESS = "success";
private static final String TAG_PRODUCT = "product";
private static final String TAG_PID = "pid";
private static final String TAG_NAME = "name";
private static final String TAG_PRICE = "price";
private static final String TAG_DESCRIPTION = "description";
private static final String TAG_STATUS = "status";
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_req_info_edit);
btnSave = (Button) findViewById(R.id.btnSave);
btnCancel = (Button) findViewById(R.id.btnCancel);
requeststatus = (Spinner) findViewById(R.id.reqstatusspinner);
// Create an ArrayAdapter using the string array and a default spinner
// layout
ArrayAdapter<CharSequence> adapter = ArrayAdapter.createFromResource(
this, R.array.request_status,
android.R.layout.simple_spinner_item);
// Specify the layout to use when the list of choices appears
adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
// Apply the adapter to the spinner
requeststatus.setAdapter(adapter);
// getting product details from intent
Intent i = getIntent();
// getting product id (pid) from intent
pid = i.getStringExtra(TAG_PID);
// Getting complete product details in background thread
new GetProductDetails().execute();
// save button click event
btnSave.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View arg0) {
if(txtName.length()<2)
{
Toast.makeText(DisplayItemInfoEdit.this,"Please enter valid item name", Toast.LENGTH_LONG).show();
return;
}
if(txtPrice.length()==0)
{
Toast.makeText(DisplayItemInfoEdit.this,"Please enter item price", Toast.LENGTH_LONG).show();
return;
}
// starting background task to update product
new SaveProductDetails().execute();
}
});
// Cancel button click event
btnCancel.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View arg0) {
// return to main menu
Intent i = new Intent();
i.setClass(DisplayItemInfoEdit.this, MainMenu.class);
startActivity(i);
}
});
}
/**
* Background Async Task to Get complete product details
* */
class GetProductDetails extends AsyncTask<String, String, String> {
/**
* Before starting background thread Show Progress Dialog
* */
@Override
protected void onPreExecute() {
super.onPreExecute();
pDialog = new ProgressDialog(DisplayItemInfoEdit.this);
pDialog.setMessage("Loading product details. Please wait...");
pDialog.setIndeterminate(false);
pDialog.setCancelable(true);
pDialog.show();
}
/**
* Getting product details in background thread
* */
protected String doInBackground(String... args) {
// Building Parameters
List<NameValuePair> params = new ArrayList<NameValuePair>();
params.add(new BasicNameValuePair("pid", pid));
// getting product details by making HTTP request
// Note that product details url will use GET request
JSONObject json = jsonParser.makeHttpRequest(url_product_detials,
"GET", params);
// check your log for json response
Log.d("Single Product Details", json.toString());
try {
// json success tag
int success;
success = json.getInt(TAG_SUCCESS);
if (success == 1) {
// successfully received product details
JSONArray productObj = json.getJSONArray(TAG_PRODUCT);
// get first product object from JSON Array
JSONObject product = productObj.getJSONObject(0);
// product with this pid found
// Edit Text
txtName = (EditText) findViewById(R.id.inputName);
txtPrice = (EditText) findViewById(R.id.inputPrice);
txtDesc = (EditText) findViewById(R.id.inputDesc);
// display product data in EditText
txtName.setText(product.getString(TAG_NAME));
txtPrice.setText(product.getString(TAG_PRICE));
txtDesc.setText(product.getString(TAG_DESCRIPTION));
} else {
// product with pid not found
}
} catch (JSONException e) {
e.printStackTrace();
}
return null;
}
/**
* After completing background task Dismiss the progress dialog
* **/
protected void onPostExecute(String file_url) {
// dismiss the dialog once got all details
pDialog.dismiss();
}
}
/**
* Background Async Task to Save product Details
* */
class SaveProductDetails extends AsyncTask<String, String, String> {
/**
* Before starting background thread Show Progress Dialog
* */
@Override
protected void onPreExecute() {
super.onPreExecute();
pDialog = new ProgressDialog(DisplayItemInfoEdit.this);
pDialog.setMessage("Saving product ...");
pDialog.setIndeterminate(false);
pDialog.setCancelable(true);
pDialog.show();
}
/**
* Saving product
* */
protected String doInBackground(String... args) {
// getting updated data from EditTexts
String name = txtName.getText().toString();
String price = txtPrice.getText().toString();
String description = txtDesc.getText().toString();
String status = requeststatus.getSelectedItem().toString();
// Building Parameters
List<NameValuePair> params = new ArrayList<NameValuePair>();
params.add(new BasicNameValuePair(TAG_PID, pid));
params.add(new BasicNameValuePair(TAG_NAME, name));
params.add(new BasicNameValuePair(TAG_PRICE, price));
params.add(new BasicNameValuePair(TAG_DESCRIPTION, description));
params.add(new BasicNameValuePair(TAG_STATUS, status));
// sending modified data through http request
// Notice that update product url accepts POST method
JSONObject json = jsonParser.makeHttpRequest(url_update_product,
"POST", params);
// check json success tag
try {
int success = json.getInt(TAG_SUCCESS);
if (success == 1) {
// successfully updated
DisplayItemInfoEdit.this.runOnUiThread(new Runnable() {
public void run() {
Toast.makeText(DisplayItemInfoEdit.this,"Item updated", Toast.LENGTH_LONG).show();
}
});
Intent i = new Intent();
i.setClass(DisplayItemInfoEdit.this, MainMenu.class);
startActivity(i);
} else {
// failed to update product
}
} catch (JSONException e) {
e.printStackTrace();
}
return null;
}
/**
* After completing background task Dismiss the progress dialog
* **/
protected void onPostExecute(String file_url) {
// dismiss the dialog once product updated
pDialog.dismiss();
}
}
}
错误来自以下代码行：
txtName.setText(product.getString(TAG_NAME));
txtPrice.setText(product.getString(TAG_PRICE));
txtDesc.setText(product.getString(TAG_DESCRIPTION));
答案 0 :(得分：0)
您无法从外部UI线程（mainthread）更改触摸Android UI工具包。因此，将以下行移至onPostExecute（）api：
txtName.setText(product.getString(TAG_NAME));
txtPrice.setText(product.getString(TAG_PRICE));
txtDesc.setText(product.getString(TAG_DESCRIPTION));
doInBackground() api正在另一个线程中运行。
android开发者引用：
Andoid UI toolkit is not thread-safe. So, you must not manipulate your UI from a worker thread—you must do all manipulation to your user interface from the UI thread. Thus, there are simply two rules to Android's single thread model:
Do not block the UI thread
Do not access the Android UI toolkit from outside the UI thread
点击链接了解更多详情：
http://developer.android.com/guide/components/processes-and-threads.html
答案 1 :(得分：0)
正如Sushil所说，你无法修改UI线程中的android ui工具包。您可以移动代码或实现处理程序系统，以通知主线程修改您的edittext。 基本上，您只需要创建一个处理程序，通知您执行的操作：
txtName.setText(product.getString(TAG_NAME));
txtPrice.setText(product.getString(TAG_PRICE));
txtDesc.setText(product.getString(TAG_DESCRIPTION))